
.head{
  height: 200px;
  width: 200px;
  background-color:green;
  position: relative;

  .content{
    position: absolute;
    margin: 10px;
    background-color:blue;
  }
  &.borter{ //&引用上一级的元素吗,会覆盖
   color: red
  }
}
.head2{
  & > { //选中head2的所有子元素
    color:red;
   }
}
.head4{
  font-size: 22px;
  background-color:pink;
  .inner1{
    color: blue;
    background-color: red;
  }
  &.inner2{
    color: red;
    font-size: 12px;
    background-color:blue;
  }
}

.a{
  & > :first-child{
    color: red;
  }
  .inline{
    cursor: pointer;
    background-color:pink;
    // display: inline;
  }
}
.inline{
  width: 300px;
  height: 300px;
  background-color: pink;
  margin-left: 50px;
  .inline1{
    height: 30px;
    border: 1px solid red;
    position: relative;
  }
  .inline2{
    border: 1px solid green;
    position: absolute;
    top: 30px;
    display: inline;
    z-index: 999;
  }
}
